Figure 3.

LoVo-S and LoVo-R were cultivated for 24 h on a Millipore filter with 5 µm pores covered by Matrigel at standard concentration mimicking the BM. LoVo-S cells show large and very flattened polygonal cells (10–20 µm) in tight contact with each other, but also a few globular ones (10 µm in diameter), which grow on the flattened ones (A). Sparse microvilli and a few vesicles are observable on their surface (B,C). Only a few (ca 3%) of the polygonal cells developed a conic/funnel shape, which suggests they were trying to invade the Matrigel (B). All LoVo-R cells appear like grouped cobblestone-shaped cells (10–20 µm) with a very flattened upper cytoplasmic surface and no tight contacts as an intercellular space wide 2–5 µm are always visible. Densely distributed microvilli and microvesicles are evident on their cytoplasmic surface. (D–F). Bar = 100 µm (A,D) Bar = 10 µm (B,C,E,F).